Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English   Periodicity: 4 times per year   Open access peer reviewed journal

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I. M. Vyshnevskyi¹, V. O. Zheltonozhskii¹, A. M. Savrasov¹, E. P. Rovenskykh^{1, 2}, V. A. Plujko^{1, 2}, O. I. Davidovskaya¹, O. M. Gorbachenko<sup>2

1</sup>Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine
²Nuclear Physics Department, Taras Shevchenko National University, Kyiv, Ukraine

Abstract: The isomeric yield ratios of ¹³³Te, ¹³⁴I, ¹³⁵Xe in photofission of ²³⁵U with bremsstrahlung with the endpoint energy E_e = 17 MeV are measured. The contributions to the isomeric yield ratios produced by β-decay from nuclei of parent isobaric chain are taken into account. The distribution and average value of angular momentum of the primary fission fragments are determined by the statistical model analysis. The codes EMPIRE 3.2 and TALYS 1.4 are applied for calculations of gamma-transitions to the isomeric and ground states. Dependence of determined distributions and average values of angular momentum on shapes of the radiative strength functions and the nuclear level densities are studied.

Keywords: isomeric yield ratios, photofission, statistical model analysis, average angular momentum.

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